EURURO Vol. 72 No. 5

Re: Incontinence Medication Response Relates to the

Female Urinary Microbiota

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Thomas-White KJ, Hilt EE, Fok C, et al

Int Urogynecol J 2016;27:723

–

Expert's summary:

The authors analyzed the female urinary microbiota (FUM) in

74 women before and after solifenacin treatment for non-

neurogenic urgency urinary incontinence (UUI). A control

group of 60 asymptomatic women was also included. Cathe-

terized urine specimens were analyzed for bacterial DNA

using high-throughput sequencing and were cultured using

an expanded quantitative urine culture (EQUC) technique. At

baseline before treatment, UUI subjects had greater FUM

diversity and more bacteria cultured compared to control

subjects. Subjects who did not respond to solifenacin had

greater FUM diversity and more bacteria cultured at baseline

compared to responders. The study suggests that greater FUM

diversity and more urinary bacteria detected with EQUC pre-

dict failure to solifenacin.

Expert's comments:

This group reported in 2012 that urine specimens from

asymptomatic women were not sterile

[1] .

Since then, there

has been burgeoning interest in studying the FUM in relation

to benign functional bladder disorders including UUI, overac-

tive bladder (OAB), urinary tract infections (UTIs), and inter-

stitial cystitis/bladder pain syndrome. The senior authors

opined that the discovery of the FUM represents a

“

paradigm

shift

”

in this field

[2]

. However, one must keep in mind that

understanding the clinical significance of the FUM requires an

equivalent understanding of bladder urothelial biology. Why?

Urothelial responses to FUM are absolutely necessary since the

bladder urothelium is where the host interacts with the FUM;

if the host does not react to the FUM, there would be no

bladder symptoms and no

“

disease

”

or condition. So which

urothelial mechanism might be important in responding to

the FUM? An answer can already be inferred from this

2016 study. Estrogen status was not matched between the

control (43% estrogen negative) and UUI (88% estrogen nega-

tive;

0.001) subjects, and this could be a reason why FUM

diversity and cultureable bacteria differed between the

groups. The importance of estrogen in UTI and OAB has been

demonstrated in several studies. Increasing host estrogen

signaling via vaginal estriol cream decreased the risk of recur-

rent UTIs in post-menopausal women

[3]

. Estradiol, via estro-

gen receptor

, augmented urothelial host defense responses

to uropathogenic bacteria

[4]

. Vaginal estradiol cream by itself

was as effective as tolterodine in ameliorating OAB symptoms

[5]

. Taking into account these observations, an important

question to answer is how urothelial estrogen signaling might

alter the FUM. As we move forward, we should be reminded

that investigations into host urothelial responses are just as

critical as a highly granular understanding of the FUM. Both

sides of the equation need to be solved to see the complete

picture.

Conflicts of interest:

The author has nothing to disclose.

References

[1]

Wolfe AJ, Toh E, Shibata N, et al. Evidence of uncultivated bacteria in the adult female bladder. J Clin Microbiol 2012;50:1376 – 83

[2]

Brubaker L, Wolfe A. The urinary microbiota: a paradigm shift for bladder disorders? Curr Opin Obstet Gynecol 2016;28:407 – 12

[3]

Raz R, Stamm WE. A controlled trial of intravaginal estriol in postmenopausal women with recurrent urinary tract infections. N Engl J Med 1993;329:753 – 6

[4]

Luthje P, Brauner H, Ramos NL, et al. Estrogen supports urothelial defense mechanisms. Sci Transl Med 2013;5:190ra80

[5]

Ellington DR, Szychowski JM, Malek JM, Gerten KA, Burgio KL, Richter HE. Combined tolterodine and vaginal estradiol cream for overactive bladder symptoms after randomized single-therapy treatment. Female Pelvic Med Reconstr Surg 2016;22:254 – 60

Toby C. Chai

Department of Urology, Department of Obstetrics, Gynecology &

Reproductive Sciences, Yale University School of Medicine,

New Haven, CT

[1_TD$DIFF]

[2_TD$DIFF]

[3_TD$DIFF]

USA

E-mail address:

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toby.chai@yale.edu . http://dx.doi.org/10.1016/j.eururo.2017.06.014

Re: Multicenter Investigation of the Micro-organisms

Involved in Penile Prosthesis Infection: An Analysis of

the Efficacy of the AUA and EAU Guidelines for Penile

Prosthesis Prophylaxis

Gross MS, Phillips EA, Carrasquillo RJ, et al

J Sex Med 2017;14:455

–

Experts

’

summary:

Gross et al conducted a multi-institution analysis of wound

cultures retrieved at the time of explant/revision surgery for

an infected penile prosthesis. The authors noted higher prev-

alence of Gram-negative bacteria, anaerobes, methicillin-re-

sistant

Staphylococcus aureus

(MRSA), and fungal organisms.

The manuscript analyzes and comments on the effectiveness

of current American Urological Association and European

Association of Urology anti-microbial guidelines in targeting

the organisms that cause prosthetic infections.

Experts

’

comments:

Placement of a penile prosthesis remains the treatment of

choice for men who have erectile dysfunction refractory to

medical treatment. Device infection remains a devastating

complication, and occurs in 1

–

3% of new implants and up

to 10% of revision procedures

[1]

. Diabetes, immunosuppres-

sion, spinal cord injury, and revision surgery have been asso-

ciated with a higher rate of infection. Mulcahy

[2]

first

reported on successful use of a salvage procedure in which

a new prosthesis is placed after explantation of the infected

device with a thorough washout of the tissue cavities. The

introduction of infection-retardant coatings has reduced the

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